Telecommunication and other systems often require multiple clocks. While design requirements vary among systems, it is generally desirable for clock generators to minimize cost, power consumption, circuitry dimensions, complexity and jitter, among other factors having a negative impact, and to maximize functionality, performance, reliability and fault coverage, among other factors having a positive impact. Known clock generators achieve varying degrees of success with regard to such factors. Various embodiments of the present invention address some or all of the shortcomings of known multiple frequency clock generators.